Optical designs of electronic apparatus to decrease myopia progression

ABSTRACT

A soft contact lens comprises a plurality of light sources coupled to a plurality of optical elements. The plurality of light sources and the plurality of optical elements are embedded in a soft contact lens material. Each of said plurality of optical elements generates an image focused in front of a peripheral retina of a wearer. In some embodiments, each of the images is focused at a distance in front of the peripheral retina at a location, and each of the images comprises a depth of focus and a spatial resolution. The depth of focus can be less than the distance, and the spatial resolution greater than a spatial resolution of the peripheral retina at the location.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/806,326, filed Jun. 10, 2022, which is a continuation of U.S. patentapplication Ser. No. 17/250,507, filed Jan. 29, 2021, now U.S. Pat. No.11,402,662, issued Aug. 2, 2022, which is a 371 national phase ofPCT/US2019/043692, filed Jul. 26, 2019, published as WO 2020/028177 onFeb. 6, 2020, and claims the benefit under 35 U.S.C. § 119(e) of U.S.Provisional Patent Application No. 62/843,426, filed May 4, 2019, and ofU.S. Provisional Patent Application No. 62/711,909, filed Jul. 30, 2018,the disclosures of which are incorporated, in their entirety, by thisreference.

BACKGROUND

Myopia, or near-sightedness, is a refractive error in which far objectsare focused anterior to the retina. This can be related to the axiallength of the eye. In general, a 1.0 mm increase in axial length of theeye corresponds to an increase in myopia of 2.5 Diopters (“D”).

Spectacle lenses, contact lenses and refractive surgery can be used totreat refractive errors of the eye such as myopia. Although theseapproaches can be effective in treating myopia, the eye may continue togrow axially, such that the amount of myopia continues to increase. Therelatively high prevalence of myopia has prompted studies to understandthe underlying mechanisms of axial growth and the development ofpossible treatment directed to axial growth.

While myopia is known to have genetic causes, the dramatic increase inthe incidence of myopia cannot be explained by genetic factors alone;rather, they must be interpreted simply as the remarkable ability of thevisual system to adapt to altered environmental conditions, specificallya shift in visual habits from long to short distances and from open toenclosed spaces.

Although pharmaceutical treatments have been proposed to treat myopiaassociated with axial length growth, these treatments can have less thanideal results in at least some instances. While atropine and othermuscarinic agents can slow myopia progression, possible concerns aboutpost treatment rebound effects and the short and long-term side effectsassociated with prolonged treatment may have discouraged the widespreaduse of these drugs.

Some studies suggest a role for retinal defocus in myopia progression.Animal studies have demonstrated that refractive development and axialgrowth can be regulated by visual feedback associated with the eye'seffective refractive status. Work in relation to the present disclosuresuggests that visual signals in the periphery of the retina caninfluence ocular shape and axial length in a manner that is independentof central vision.

Work in relation to the present disclosure suggests that the retinalshell becomes more aspheric as the eye becomes more myopic. Examples ofimage shells on the retina with myopic eyes and traditional correctionare described in Cooper, J, “A Review of Current Concepts of theEtiology and Treatment of Myopia” in Eye & Contact Lens, 2018; 44: pp231. With traditional spherical lenses, the peripheral aspheric retinaof the myopic eye receives light focused behind the retina while lightis focused at the center of the retina, which can trigger a growthsignal because the peripheral light is focused behind the retina,similarly to an eye with insufficient axial length. A conventionalspherical or toric lens (e.g. a contact lens or a spectacle lens)generally cannot generate an image shell that matches the optimum shaperequired for refractive correction that would stop the growth signal tothe retina to become even more myopic. One approach has been to providean aspheric lens that focuses light onto the peripheral regions of theaspheric retina.

Previous refractive correction devices to prevent myopia progression mayproduce less than ideal results in at least some instances. Therefractive correction to provide appropriate focus at the peripheralretina can require a highly aspheric image shell, that can be created bya highly aspheric optic. Unfortunately, such an aspheric optic cangenerate a central image with a substantial aberration, compromising farvision and reducing quality of vision of the wearer in at least someinstances. One approach has been to limit the amount of asphericity toabout 2 D or less in order to provide distance vision withoutsignificant aberrations to central vision, but this limitation on theamount of asphericity can also limit the amount of correction toperipheral portions of the retina, which can lead to a less than idealtreatment in some instances.

Studies in animal models as well as clinical studies have suggested thatthe retina can distinguish a “plus blur” from a “minus blur”, or imageblur caused by a myopic defocus from a hyperopic defocus, possibly byutilizing longitudinal chromatic aberration as a guide, since the signof the longitudinal chromatic aberration will be opposite, depending onwhether the image blur is hyperopic or myopic. However, prior clinicalapproaches may not have not adequately addressed chromatic aberration todecrease myopia progression in at least some instances.

Therefore, a new approach is needed to decrease myopia progression thatcan meet the expectation of comfort and performance by young wearerswhile providing an effective peripheral hyperopic defocus.

SUMMARY

In some embodiments, a contact lens comprises a light source 30 andoptics to form an image in front of the retina with one or more of anappropriate resolution, depth of focus or diffraction. The image formedin front of a region of the retina may comprise a resolution finer thanthe resolution of the retina at the region. The light beam can bedirected to the region of the retina at an angle relative to the opticalaxis of the eye, so as to illuminate an outer portion of the retina witha resolution finer than the corresponding location of the retina. Thedepth of focus can be configured to illuminate the retina with anappropriate amount of blurring of the image on the retina, and thediffraction of the spot can be appropriately sized to provide resolutionof the image formed in front of the retina finer than the resolution ofthe retina.

In accordance with some embodiments, a soft contact lens comprisesmicro-displays located away from a center of the contact lens and towarda periphery of the contact lens, in which each of the micro-displays iscoupled to a micro-lens array located posteriorly to the micro-display.The micro-displays may comprise an OLED (organic light emitting diode)or an array of micro-LEDs. The micro-lens arrays can be opticallycoupled with the displays to efficiently collect light from themicro-displays, and collimate the light and/or converge the light beforeprojecting the light into the entrance pupil. The virtual images createdby these displays can be myopically defocused and placed symmetricallyin a plurality of regions on the retina, such as four sectors(nasal-inferior, nasal-superior, temporal-inferior andtemporal-superior). The micro displays can be located away from theoptical center of the lens by a distance within a range from 1.5 mm to4.0 mm, such as 2.5 mm to 3.5 mm. The central optical zone 14 of thecontact lens can be configured to provide emmetropic vision for thewear, and may have a diameter within a range 3.0 to 5.0 mm. Eachmicro-display can generate a retinal image with an appropriate shape,such as circular or arcuate and at an angle of about 20-60 degrees atthe fovea. In some embodiments, the retinal images are formed at theperipheral retina at an eccentricity in the range of 15 degrees to 40degrees, for example within a range from 20 to 30 degrees. The contactlens may comprise an electronic control system mounted with themicro-displays on a flexible transparent sheet of material such asplastic and other components.

In some embodiments, the micro displays 12 may comprise OLEDs with pixelsizes within a range from 2.0 micrometers (microns) to 5.0 microns, witha pitch in the range of 2.0-10.0 microns. In some embodiments, themicro-displays embedded in the contact lens comprise micro-LEDSilluminating an object, such as a thin film placed in front of it andtoward the eye. The micro-displays may comprise polychromatic ormonochromatic micro-displays. The polychromatic images can be formed byRGB pixels in the OLED or micro-LEDS of different colors, organized inarrays so as to form an RGB display. In some embodiments, the wavelengthfor stimulation of change in axial length is within a range from about450 nm to about 560 nm, and can be near 500 nm, the peak wavelength ofstimulation of rods in the eye, although other wavelengths may be used.

In some embodiments, an optical configuration comprises one or morelight sources coupled to a light processing structure that comprises oneor more of collimating lenses, mirrors, lightguides, waveguides, orholographic mirrors. The light processing structure images the one ormore light sources so as to a project an image of the light source infront of the peripheral retina, such that the focus of the image is infront of the retinal surface. In some embodiments, the opticconfiguration is placed at or near the anterior surface of the contactlens, and rays from the micro-displays are focused by the contact lens.The contact lens can be configured to provide refractive correction tothe wearer, and the display optics configured to provide additionalfocus to provide the defocused image of the micro-display on the retina.In some embodiments, the amount defocus is in within a range from about2.00 Diopter (D) to 6.00 D, and can be within a range from about 2.0 Dto 4.0 D.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the features, advantages and principles of thepresent disclosure will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, and theaccompanying drawings of which:

FIG. 1 shows a soft contact lens, in accordance with some embodiments;

FIG. 2A shows OLED micro displays mounted on the inner surface of softcontact lens, optically coupled with micro lens arrays for projectingimages with myopic defocus on the periphery of the retina of a wearer,in accordance with some embodiments;

FIG. 2B shows a soft contact lens comprising a plurality of lightsources and optics and associated circuitry, in accordance with someembodiments;

FIG. 2C shows mechanical integration of the function of the componentsof the contact lens as in FIG. 2B;

FIG. 3 shows an optical configuration in which the optical path lengthis increased by folding back the optical path using two mirrors, inaccordance with some embodiments;

FIG. 4 shows a ray tracing simulation of the optical configuration shownin FIG. 3 , in which the Liu Brennan eye model has been used to computethe retinal image, in accordance with some embodiments;

FIGS. 5A and 5B show analysis of retinal image quality generated by theoptic configuration of FIG. 3 ;

FIG. 6 shows analysis of depth of focus of the optic configuration shownin FIG. 3 ;

FIG. 7 shows the MTF for the analysis of FIG. 6 .

FIGS. 8A and 8B show an optical configuration comprising a lens to focuslight onto the retina, in accordance with some embodiments;

FIG. 9 shows analysis of retinal image quality generated by the opticconfiguration shown in FIGS. 8 and 8B, in accordance with someembodiments;

FIG. 10 shows analysis of depth of focus of the optic configurationshown in FIGS. 8A and 8B.

FIGS. 11A and 11B show a light-pipe in order to increase the opticalpath length, in accordance with some embodiments;

FIG. 12 shows soft contact lens with embedded light sources, optics andelectronics, in accordance with some embodiments;

FIG. 13 shows a ray tracing simulation of the peripheral retinal imageformed by a combination of a microscopic light source and a micro-optic,in accordance with some embodiments;

FIG. 14 shows four object points used to simulate image quality usingray tracing for a light source comprising four simulated object points,in accordance with some embodiments;

FIG. 15 shows the quality of a peripheral image generated by areflective optic, in which Modulation transfer functions (MTF) of allthe object points are substantially coincident, in accordance with someembodiments;

FIG. 16 shows depth of focus of the peripheral image formed by thereflective optic, in accordance with some embodiments;

FIG. 17 shows the effect of myopic blur on image resolution of theperipheral retinal image formed by the reflective optic, as measured bychange of the magnitude of MTF at a single spatial frequency (20/200 or10 line pair per mm “lp/mm” or 10 arc min) as a function of themagnitude of myopic defocus for the reflective optical design, inaccordance with some embodiments;

FIG. 18 shows MTF plots of the retinal image formed by the refractiveoptic for the four object points shown in FIG. 14 , in accordance withsome embodiments;

FIG. 19 shows depth of focus of the image formed by the refractiveoptic, in accordance with some embodiments;

FIG. 20 shows MTF computed for a single spatial frequency (20/200 or 10lp/mm, or 10 arc min) as a function of myopic defocus, in accordancewith some embodiments;

FIG. 21 shows MTF plots of the four object points in FIG. 14 forembodiments comprising a miniature lightguide, in which a substantialdifference in image quality exists between sagittal and tangentialplanes, indicating non-symmetrical aberrations, in accordance with someembodiments;

FIG. 22 . Depth of focus of the peripheral retinal image projected bythe lightguide optic, in accordance with some embodiments;

FIG. 23 shows MTF plots at a single spatial frequency (20/200) plottedagainst the magnitude of myopic defocus of the peripheral image on theretina for embodiments with light guides;

FIG. 24 shows a comparison of depths of focus of the peripheral imagesgenerated by the three projection systems, comprising a refractiveoptic, a reflective optic and a lightguide optic, in accordance withsome embodiments;

FIG. 25 shows depth of focus of the retinal image generated by areflective optic design, in accordance with some embodiments and

FIG. 26 shows MTF values at a single spatial frequency plotted againstmagnitude of myopic defocus for the peripheral image created by thereflective optic design of FIG. 25 , in accordance with someembodiments.

DETAILED DESCRIPTION

In accordance with some embodiments, a soft contact lens comprisesperipheral micro-displays, each of which is fronted eye side by amicro-lens array. The micro-displays may comprise an OLED (organic lightemitting diode) or an array of micro-LEDs. Light emitted by thesedisplays is typically Lambertian. The micro-lens arrays are opticallycoupled with the displays, so that they can efficiently extract lightfrom the micro-displays, collimate the light and focus it beforeprojecting them into the entrance pupil. The virtual images created bythese displays will be myopically defocused and will be placedsymmetrically in the four sectors (nasal-inferior, nasal-superior,temporal-inferior and temporal-superior), in some embodiments. The microdisplays will be located away from the optical center of the lens by adistance within a range from 1.5 mm to 4.0 mm, preferably 2.5 mm to 3.5mm, in some embodiments. The central optic of the contact lens can beselected to bring the wearer as close to emmetropia as possible, and mayhave a diameter within a range 3.0 to 5.0 mm. Each micro-display will becircular, rectangular or arcuate in shape and will each have an areawithin a range from 0.01 mm² to 8.0 mm², for example within a range from0.04 mm² to 8.0 mm², for example within a range from 1 mm² to 8 mm², orpreferably within a range from 1.0 mm² to 4.0 mm², in some embodiments.In some embodiments, each of the plurality of micro-displays comprisesthe light source, the back plane and associated electronics with thedimensions and shapes as described herein. The contact lens will have anelectronic control system as well as the micro-displays mounted on aflexible transparent sheet of plastic. The electronic system maycomprise an ASIC or a microcontroller, a rechargeable Lithium ion solidstate battery, a voltage ramping module e.g., a buck boost converter, aflash memory and an EEPROM, an RFID module to provide wirelessrecharging, or an antenna preferably disposed radially along the edge ofthe contact lens, and any combination thereof. The contact lenscomprises a biocompatible material, such as a soft hydrogel or siliconehydrogel material, and may comprise any material composition that hasproven to be compatible with sustained wear on the eye as a contactlens.

In some embodiments, virtual images focused at a target distance fromthe peripheral retina, equivalent to a myopic defocus. Rays formingthese images do not come from outside environment but from themicro-displays themselves, so the optics of the micro-lens arrays can besolely designed to process the rays emanating from the micro-displays.The area of each of these micro-displays and micro-lens arrays in frontof each is small, so the obscuration of the real image is small, asshown in FIGS. 1 and 2 .

The device as described herein can give each caregiver substantialflexibility in setting and testing such parameters for an individualpatient, then refining the preferred parameters of treatment based onobservations of patient response.

Some embodiments comprise a contact lens of diameter 14.0 mm, with anedge zone of 1.0 mm and a peripheral zone 16 whose inner diameter is 6.0mm and outer diameter is 12.0 mm. The overall diameter of the lens maybe in the range of 13.0 mm and 14.5 mm, preferably 13.5 and 14.5 mm. Thecentral optical zone 14 is designed to cover the pupil of all wearersunder all illumination conditions, and should therefore have a diameterin the range of 5.0 mm and 8.0 mm. The peripheral or the blend zone isprimarily designed to provide a good fit to the cornea, including goodcentration and minimum decentration. The central optical zone 14 isdesigned to provide emmetropic correction to the wearer and may beprovided with both spherical and astigmatic correction (FIG. 1 ).Contact lens designs suitable for incorporation in accordance withembodiments disclosed herein are described in Douthwaite, D. A.,“Contact lens optics and lens design”, 3^(rd) edition, 2006; ISBN978-0-7506-88-79-6; Butterworth-Heinemann.

In some embodiments, the inner surface of the contact lens is embeddedwith a set of four micro-displays coupled eye side with micro-lensarrays of the same size. The function of the micro-lens arrays is tocollimate the light being emitted by the micro-displays, collimate it,and focus it at a focus that is designed to be in the front of the eye,to provide hyperopic defocus. The micro-displays can be sized in manyways, and each of these micro-displays is only about 0.04 mm² to 2 mm²in area, for example from 1 mm² to 2 mm² in area, so that these displayscover less than 1% of the contact lens optic, in some embodiments. Eachof the displays will generate about 30-50 cd/m² or greater ofillumination, quite sufficient for forming a relatively bright image atthe focus of each of these micro-displays. The focused images willappear approximately 1.5-2.5 mm in front of the peripheral retina, sincethey will be designed to be myopic by about 2.0 D to 5.0 D, for example2.0 D to 4.0 D, or preferably 2.5 D to 3.5 D, for example.

In some embodiments, the micro displays may be OLEDs with pixel size of2.05.0 microns, with a pitch in the range of 2.0-10.0 microns. In someembodiments, the micro-displays embedded in the contact lens asdescribed herein will consist of micro-LEDS illuminating an object, suchas a thin film placed in front of it, eye side. The micro-displays maybe polychromatic or they may be monochromatic. The polychromatic imagesare formed by RGB pixels in the OLED or micro-LEDS of different colors,organized in arrays so as to form an RGB display. Data on wavelengthdependence of axial length alteration of the projected hyperopic ormyopic image at the peripheral retina are lacking. A preferredwavelength for stimulation of change in axial length is 500 nm, the peakwavelength of stimulation of rods in the eye, although other wavelengthsmay be used.

The amounts and location of illumination on outer locations of theretina to provide a therapeutic benefit can be determined by one ofordinary skill in the art without undue experimentation in accordancewith the teachings disclosed herein. The length and duration ofperipheral stimulation can be determined, for example optimized, basedon available preclinical data in animal models. For example, somestudies suggest that changes in axial length in animal models can beobtained on repeated application of defocus stimuli, in preference to asingle sustained period of equivalent duration of imposed defocus.Examples of studies with information on illumination changes in axiallength suitable for incorporation in accordance with the embodimentsdisclosed herein include: Wallman, J., et al, “Homeostatis of eye growthand the question of myopia”, in Neuron, 2004; 43: pp 447;Benavente-Perez, A, et al, “Axial Eye Growth and Refractive ErrorDevelopment Can Be Modified by Exposing the Peripheral Retina toRelative Myopic or Hyperopic Defocus” In IOVS 2014; 55: pp 6767; andHammond, D. S., et al, “Dynamics of active emmetropisation in youngchicks—influence of sign and magnitude of imposed defocus” in OphthalmicPhysiol Opt. 2013; 33: pp 215-222.

Work in relation to the present disclosure suggests that the durationand distribution of application of peripheral myopic defocus will dependon individual physiology and the precise shape of the retina. Anembodiment comprises a reprogrammable MCU or ASIC controlling theoperation of the micro-displays, and a real time clock that will enableadjustment of the treatment duration and periodicity by the caregiver,throughout the treatment. This embodiment also enables the caregiver totest whether nocturnal stimulation (sustained or repeated sequence ofshort pulses) has an efficacy for certain individuals.

In some embodiments, the electronic components are populated on aflexible thin film on which interconnects and electrical bus aredeposited by means of vapor deposition or a 3D printing process. In someembodiments, the electronics and the micro-displays are further coatedwith a flexible stack of thin barrier film, such as a stack of ParalyneC and SiO_(x) film of total thickness 5-10 microns, developed by Coat-X,a corporation located in Neuchatel, Switzerland.

Some embodiments of the device deploy a set of one to eightmicro-displays, each circular or arcuate in shape, and they are disposedradially on the inner surface of the contact lens, all at the samedistance from the optical center of the lens. In one embodiment, theymay be monochromatic. In another embodiment they may be designed toprovide white light output. In a third embodiment, they may be designedto output illumination matched to the retinal sensitivity. Thesemicro-displays are operated and controlled by a reprogrammablemicrocontroller (MCU) or an ASIC.

In some embodiments, the contact lens is worn during sleep, and themicro-displays are programmed to operate only when the wearer is asleep.Such a programmed stimulation of reduction of the axial length willinterfere minimally with daily activities, including reading andcomputer work. The contact lens may even be removed during daytimeactivities, while it is fit on the cornea just before going to sleep.Other embodiments may utilize other programming algorithms, for examplea combination of daytime and nighttime stimulations.

In some embodiments, the contact lens may be a daily disposable lens,obviating the need for disinfecting and cleaning the lens or rechargingit. Another embodiment consists of a contact lens of planned replacementmodality.

In some embodiments, each micro-display (1 mm² to 4 mm²) will consumeabout 10 microwatts of electrical energy. In these embodiments, a set offour micro-displays may use about 125 microwatt-hours of electricity for2 hours of operation, so that the total daily energy consumption forthis design will be expected to be 0.2 milliwatt-hour. In someembodiments, each micro-display comprises a cross-sectional area withina range from about 0.04 mm² to 4 mm² and consumes about 10 microwatts ofelectrical energy. In some embodiments, the electrical power is suppliedby a rechargeable, solid state lithium ion battery. A bare die solidstate rechargeable lithium ion battery, marketed by Cymbet Corporation,may be populated on the same flexible substrate as the electronics ofthe lens. For example, a 50 uAH rechargeable lithium ion solid filmbattery has dimensions of 5.7×6.1 mm×0.200 mm (Cymbet CorporationCBC050). In some embodiments, the battery comprises sufficient mass tostabilize the contact lens. For example, the battery can be located onan inferior position of the lens in order to stabilize the lens withgravity. The inferiorly located battery may comprise a mass sufficientto decrease rotational movement such as spinning when the wearer blinks.

In some embodiments, an electronic contact lens projects a 2.0-5.0 Dmyopically defocused image at the retinal periphery, while maintainingexcellent vision at the center.

In some embodiments, the electronic soft contact lens comprisesmicroscopic light sources and microscale optics embedded at theperiphery of the lens optic. The contact lens optic can be designed toprovide excellent vision at the central retina, while the outer lightsources project images at the outer portions of the retina that aremyopically defocused. In some embodiments, the light sources comprisemicro displays. In some embodiments, the outer images formed anterior tothe retina may to stimulate the retina to move forward, reducing theaxial length and deepening the vitreous compartment. In some embodimentsthe contact lens is configured to one or more of decrease myopiaprogression, substantially stop myopia progression, or reverse myopia inthe eye wearing the lens. In some embodiments, the contact lens can beconfigured for extended wear and replaced once a month, for example. Thecontact lens can be replaced more frequently or less frequently, forexample, once a week, or once every three months. In some embodiments,the contact lens is designed to be worn by teens and young adults, whocan be at greater risk of myopia progression than people of other ages.

In some embodiments, the amount of myopic defocus of the peripheralimage is within a range from about 2.0 D to about 5.0 D, for examplefrom about 2.5 D to about 5 D. Based on the teachings disclosed herein aperson of ordinary skill in the art can conduct studies such as clinicalstudies to determine appropriate amounts of defocus, illuminationintensities and times of illumination. In some embodiments, one or moreof the amount of defocus, the retinal locations of the retinalillumination or the times of illumination can be customized to anindividual, for example in response to physiological characteristics ofthe individual patient. The duration of treatment can be within a rangefrom 1 to 3 years, for example about 2 years. In some embodiments, thetreatment is performed with a number of lenses within a range from about10 lenses to about 40 lenses, for example from about 10 lenses to about30 lenses. The prescription of the optical zone 14 comprising thecentral lens optic may change with time during treatment, and theprescription of the contact lens can be changed is appropriate. Thecontact lenses as disclosed herein may also be subsequently worn asneeded, for example if myopia progression returns.

The electronic contact lens can be configured in many ways to correctrefractive error of the wearer. In some embodiments, the contact lenscomprises a plurality of micro-displays that emit light near a peripheryof the optical zone 14 of the contact lens, a plurality of micro-opticsto collect, collimate and focus the light rays emanating from the lightsources, a miniaturized rechargeable solid state battery to providepower to the light sources (e.g. a Lithium ion solid state battery), anantenna to wirelessly receive power to recharge the battery, and amicro-controller to control actuating and controlling functions, and amemory to store data or software instructions.

In some embodiments, the outer image comprises a peripheral imagelocated outside the macula, for example within a range from about 20degrees to about 30 degrees eccentric to the fovea.

The contact lens can be configured in many ways with a plurality ofoptics such as micro-optics to collect light from a plurality of lightsources (e.g. microscope light sources) and form an image anterior to anouter portion of the retina such as anterior to a peripheral portion ofthe retina. In some embodiments, the plurality of optics comprises oneor more of a light-pipe and a reflective component, such as mirrors, forexample microscopic mirrors.

The device as described herein can be used to treat advancement ofrefractive error such as myopia. In some embodiments, each caregiver hassubstantial flexibility in setting and testing parameters for anindividual patient, then refining the preferred parameters of treatmentbased on observations of patient response.

In some embodiments, the optical design of the refractive properties ofthe contact lens substantially unaltered and can be configured in manyways. For example, the central optical zone 14 of the contact lens canbe optimized for best correction of the far image at the fovea, whileproviding images at the periphery of the retina that are anterior to theimage shell of the contact lens optic, so as to decrease the advancementof refractive error. In some embodiments, the light sources may comprisea surface area of no more than 2 mm² of the optical surface, and thesize of the optical surface to correct refractive error can be within arange from about 25 mm² to about 50 mm², which can decrease the effectof the light source on vision. An intensity of the peripheral image thatcan be provided independently of the level of ambient illumination, andthe intensity of the light sources can be adjusted over several ordersof magnitude by selecting light sources of appropriate power. The softcontact lens can be configured to provide appropriate amounts ofillumination response to input from the wearer or a health careprovider.

FIG. 1 shows micro-displays 12 embedded in the contact lens 10. The softcontact lens 10 comprises an optical zone 14 configured to provide farvision correction to the wearer, for example with a visual acuity of20/20 or better. The micro-displays 12 can be configured to provide theimages in front of the peripheral portion of the retina as describedherein. This configuration can allow the user to have good visual acuitywhile receiving therapy from the images focused in front of the retinaas described herein.

The micro-displays 12 may comprise micro-LEDS illuminating an object,such as a thin film placed in front of it, eye side. The light emittedby these micro-displays 12 can be Lambertian and directed to an opticalelement such as a lens to direct the light beam toward the retina. Thecontact lens 10 comprises a diameter suitable for placement on an eye.For example, the contact lens 10 may comprise a diameter within a rangefrom about 10 mm to 15 mm, for example 14.0 mm. The contact lens 10 maycomprise a plurality of embedded micro-displays 12. Each of theplurality of micro-display 12 can be optically coupled to an opticalconfiguration that collects light emitted by the micro-display 12 andprojects an image on or in front of the retina of the wearer at aspecified eccentricity. Each of the displays 12 can generate anillumination within a range from about 1 cd/m² to about 50 cd/m². Theamount of illumination can be sufficient for forming a relatively brightimage at the focus of each of these micro-displays 12.

In some embodiments, the amount of illuminance is intermediate betweenphotopic and mesopic levels of illumination and intermediate levels ofsensitivity of rods and cones. The preferred amount of illumination canbe within a range from about 0.1 cd/m² to about 10 cd/m², preferablybetween 0.5 cd/m² to 5 cd/m² at the pupil plane. This amount ofilluminance may correspond to an amount of light between moonlight andindoor lighting, for example. In some embodiments, the amount ofillumination corresponds to mesopic vision.

In some embodiments, the micro-displays 12 can comprise light sourcesthat emit polychromatic light composed of light of differentwavelengths. In other embodiments, the light sources emit monochromaticlight. In some embodiments, the wavelength of the monochromaticillumination can be in the range of 500 nm to 560 nm, preferably from500 nm to 530 nm, more preferably from 500 nm to 510 nm.

In some embodiments, the polychromatic light sources provide chromaticcues to the peripheral retina. The chromatic cues may comprise negativechromatic aberration. In some embodiments, a poly chromatic light beamis focused anterior to the retina, in which the polychromatic light beamcomprises a positive chromatic aberration prior to an image plane 35 ora focal plane and a negative chromatic aberration after the image plane35 or focal plane so as to illuminate the retina with a negativechromatic aberration.

While the polychromatic illumination can be configured in many ways, insome embodiments, the polychromatic illumination comprises redillumination, blue illumination and green illumination, although otherwavelengths of light may be used.

In some embodiments, the projected images appear approximately 1.5 mm toabout 2.5 mm in front of the peripheral retina, since they will bedesigned to be myopic by about 2.0 D to 4.0 D, preferably 2.5 D to 3.5D. In general, 1 mm in front of the retina corresponds to about 2.5 D ofmyopia, for example about 2.7 D of myopia.

This approach of peripheral stimulation of change in axial lengththrough thickening or thinning of the choroid can be based on repeatedand confirmed observations of the efficacy of application localizedhyperopic or myopic defocus in stimulating change in the axial length ofthe eye 11. The length and duration of peripheral stimulation can bebased on available preclinical data in animal models as is known to oneof ordinary skill in the art. For example, the rate of change in axiallength can obtained on repeated application of defocus stimuli, inpreference to a single sustained period of equivalent duration ofimposed defocus.

In some embodiments, the duration and distribution of application ofperipheral myopic defocus depends on individual physiology and the shapeof the retina. In some embodiments, the contact lens 10 comprises aprogrammable processor such as a microcontroller unit (MCU) orapplication specific integrated circuitry (ASIC) for controlling theoperation of the micro-displays 12. The contact lens 10 may comprise areal time clock to adjust the treatment duration and periodicity by thecaregiver, and the treatment duration and periodicity may be providedthroughout the treatment. In some embodiments, the caregiver testswhether nocturnal stimulation (sustained or repeated sequence of shortpulses) has an efficacy for certain individuals.

FIG. 2A shows OLED micro displays 12 mounted on the inner surface ofsoft contact lens 10, optically coupled with micro lens arrays forprojecting images with myopic defocus on the periphery of the retina ofa wearer.

FIG. 2B shows a soft contact lens 10 comprising a plurality of lightsources and optics and associated circuitry, in accordance with someembodiments. The contact lens 10 comprises a plurality of projectionunits 18. Each of the plurality of projection units 18 comprises a lightsource and one or more optics to focus light in front of the retina asdescribed herein. Each of the optics may comprise one or more of amirror, a plurality of mirrors, a lens, a plurality of lenses, adiffractive optic, a Fresnel lens, a light pipe or a wave guide. Thecontact lens 10 may comprise a battery 20 and a sensor 22. The contactlens 10 may comprise a flex printed circuit board (PCB) 24, and aprocessor can be mounted on the PCB 24. The processor can be mounted onthe PCB 24 and coupled to the sensor 22 and the plurality of lightsources 30. The soft contact lens 10 may also comprise wirelesscommunication circuitry and an antenna for inductively charging thecontact lens 10. Although reference is made to a battery 20, the contactlens 10 may comprise any suitable energy storage device. The softcontact lens 10 may comprise a lens body composed of any suitablematerial such as a hydrogel. The hydrogel can encapsulate the componentsof the soft contact lens 10.

The processor can be configured with instructions to illuminate theretina with the plurality of light sources 30. The processor can beprogrammed in many ways, for example with instructions received with thewireless communication circuitry. The processor can receive instructionsfor a user mobile device.

The sensor 22 can be coupled to the processor to allow the user tocontrol the contact lens 10. For example, the sensor 22 can beconfigured to respond to pressure, such as pressure from an eyelid. Theprocessor can be coupled to the sensor 22 to detect user commands.

The electronic control system may comprise a processor such as an ASICor a microcontroller, a rechargeable Lithium ion solid state battery, avoltage ramping module e.g., a buck boost converter, a flash memory andan EEPROM, an RFID module to provide wireless recharging, or an antennapreferably disposed radially near an edge of the contact lens 10, andany combination thereof. The contact lens 10 may comprise abiocompatible material, such as a soft hydrogel or silicone hydrogelmaterial, and may comprise any material composition that has proven tobe compatible with sustained wear on the eye 11 as a contact lens 10.

FIG. 2C shows mechanical integration of the function of the componentsof the contact lens 10 as in FIG. 2B. These components can be supportedwith the PCB 24. For example, the power source such as a battery 20 canbe mounted on the PCB 24 and coupled to other components to provide apower source function 21. The sensor 22 can be configured to provide anactivation function 23. The sensor 22 can be coupled to a processormounted on the PCB 24 to provide a control function 25 of the contactlens 10. The control function 25 may comprise a light intensity setting27 and a light switch 29. The processor can be configured to detectsignal from the sensor 22 corresponding to an increase in intensity, adecrease in intensity, or an on/off signal from the sensor 22, forexample with a coded sequence of signals from the sensor 22. Theprocessor is coupled to the light projection units 18 which can comprisea light source 30 and optics 32 to provide the projection function 31.For example, the processor can be coupled to the plurality of lightsources 30 to control each of the light sources 30 in response to userinput to the sensor 22.

In some embodiments, the optic configuration 32 comprises a plurality ofmirrors configured to collect light emitted by the micro-displays 12,then direct the light beam to the pupil of the eye 11, in order to forman eccentric retinal image, as shown in FIGS. 3 and 4 . The mirrors maycollimate the light beam, or direct the light beam toward the retina 33with a suitable vergence so as to focus the light beam onto the retina33.

The specifications of the optical configuration are shown in Table 1.

TABLE 1 Basic optic parameters of the optic configuration shown in FIG.3. Value (Reflective Value (Single Lens Characteristics Design) Design)Size of the light source 10 microns 10 microns Diameter of the optic 1.1mm 0.292 mm Decentration of the light 1.75 mm 1.75 mm source from thecenter of the contact lens Wavelength 507 nm 507 nm Thickness of optic300 microns 250 microns Retinal image location 27 degrees eccentric 27degrees eccentric Size of the retinal image 200 microns 1100 microns

A comparison of the simulated image size for the optic configurationshown in FIG. 3 and the retinal resolution at 27 degrees eccentricityshows that the peripheral retina 33 at this eccentricity will be able toperceive this image.

In some embodiments, three performance attributes of the opticconfiguration include one or more of:

1. Image magnification, controlling image resolution,

2. Depth of focus, controlled by the optical path length of the opticconfiguration, and

3. Diffraction, as measured by the Airy Diameter.

The mirror assembly shown in FIG. 3 achieves a depth of focus that isless than 1 D, enabling the applied defocus of 2.0-4.0 D to be clearlyperceived by the peripheral retina 33 at the specified eccentricity(20-30 degrees).

In some embodiments, the spots size of the image focused in front of theretina 33 comprises a resolution finer than the resolution of the retina33. Retinal resolution generally decreases as a function ofeccentricity. For example, at an angle of 0 degrees of eccentricity,retinal resolution is approximately 10 micrometers. At 5 degrees ofeccentricity, the retinal resolution is approximately 30 micrometers. At20 degrees of eccentricity, the resolution is approximately 100micrometers and at 30 degrees the retinal resolution is approximately150 micrometers.

FIGS. 5A and 5B show analysis of retinal image quality generated by theoptic configuration of FIG. 3 . Images formed by three of the four lightsources 30 have been simulated. The temporal point has been omittedbecause it is symmetrical to the nasal point. The analysis shows thatthe image quality exceeds the resolving power of the retina 33 at 27degrees eccentricity. The modulation transfer function of the retinalimage created by the mirror assembly of FIG. 3 is diffraction limited,indicating that aberrations of the optical elements deployed are notcausing significant deterioration of image quality, in accordance withthis embodiment. Furthermore, the spatial resolution of the opticsexceeds the resolution of the retina 33 at the preferred image location.

FIG. 6 shows analysis of depth of focus of the optic configuration shownin FIG. 3 . Each millimeter of distance from the retina 33 represents adefocus of 2.7 D. This analysis shows that the depth of focus issufficiently small that a defocus of 0.5 mm (1.35 D) is perceivable bythe retina 33 at the point of incidence of the image (27 degreeseccentricity). Depth of focus depends on effective path length of thestimulating beam.

FIG. 7 shows the plot of MTF values against defocus shows the depth offocus of image created by each of the light sources (object).

A second embodiment comprises optics 32 comprising a converging orcollimating lens in optical coupling with light source 30, as shown inFIGS. 8A and 8B. In this configuration a lens 34, which may comprise asingle lens, is used to collimate the light output from the stimulationsource and direct it to the cornea 37 through the contact lens 10. Theeffectiveness of the collimating lens 34 depends on its refractive indexand should be sufficiently high in order to create a substantialdifference in refractive indices between the lens material and thematerial of the contact lens 10 that functions as the substrate. In thisexample, the refractive index of the embedded lens 34 has been assumedto be 2.02 (e.g., refractive index of a lanthanum fluorosilicate glassLaSF₅), although other materials may be used.

Optical performance of the embodiment of FIGS. 8A and 8B is shown inFIGS. 9 and 10 . Images formed by three of the four light sources 30have been simulated. The temporal point has been omitted because it issymmetrical to the nasal point. Each millimeter of distance from theretina 33 represents a defocus of 2.7 D. This analysis shows that thedepth of focus is substantially higher than 1 D, so that image blurcaused by a defocus of 0.5 mm (1.35 D) may not be perceivable by theretina 33 at the point of incidence of the image (27 degreeseccentricity).

The analysis shows that the image quality exceeds the resolving power ofthe retina 33 at 27 degrees eccentricity. The optical path length of thesingle lens design is much shorter in this case, therefore, imagemagnification is substantially higher (110×, as opposed to 20× for thereflective design). The spatial frequency resolution at 50% contrast(Modulus of OTF) is lower, approximately 15 line pairs per millimeter(“lp/mm”), compared with 50 lp/mm for the reflective design. Depth offocus has been estimated for this embodiment, again using Liu Brennaneye model to simulate the ocular optics, including ocular aberrations,as shown in FIG. 10 . The depth of focus is greater than 1.0 D,indicating that changes in image resolution as a function of defocus maynot be easily perceivable by the peripheral retina 33, especially sincethe resolution capability of the retina 33 at that eccentricity (20-30degrees), derived mainly from rods is relatively poor as describedherein.

A third embodiment comprises a light-pipe 36 in order to increase theoptical path length, as shown in FIGS. 11A and 11B. The light-pipe 36can provide an increased optical path length to decrease imagemagnification and retinal image size. However, depth of focus isrelatively large, and the resolution is relatively coarse (15 lp/mm at50% MTF).

Numerous other optical configurations may be considered, including theuse of a micro-lens array with a point source, use of diffractive opticsin order to use a thinner lens, generation of multiple retinal imagesusing a single point source and an optical processing unit. In all case,the three characteristics listed above may be used as metrics in orderto evaluate the suitability of a particular design.

Each embodiment disclosed herein can be combined with any one or more ofthe other embodiments disclosed herein, and a person of ordinary skillin the art will recognize many such combinations as being within thescope of the present disclosure.

The presently disclosed methods and apparatus are well suited forcombination with many types of lenses, such as one or more of: smartcontact lenses, contact lenses with antennas and sensors, contact lenseswith integrated pulse oximeters, contact lenses with phase map displays,electro-optic contact lenses, contact lenses with flexible conductors,autonomous eye tracking contact lenses, electrochromic contact lenses,dynamic diffractive liquid crystal lenses, automatic accommodationlenses, image display lenses with programmable phase maps, lenses withtear activated micro batteries, tear film sensing contact lenses, lenseswith multi-colored LED arrays, contact lenses with capacitive sensing,lenses to detect overlap of an ophthalmic device by an eyelid, lenseswith active accommodation, lenses with electrochemical sensors, lenseswith enzymes and sensors, lenses including dynamic visual fieldmodulation, lenses for measuring pyruvate, lenses for measuring urea,lenses for measuring glucose, lenses with tear fluid conductivitysensors, lenses with near eye displays with phase maps, or lenses withelectrochemical sensor chips.

A soft contact lens 10 is shown in FIG. 12 . This contact lens 10comprises a base or carrier contact lens comprising embedded electronicsand optics. The base soft contact lens 10 is made of a biocompatiblematerial such as a hydrogel or a silicone hydrogel polymer designed tobe comfortable for sustained wear. In some embodiments, the contact lens10 has a central optical zone 14 of diameter within a range from 6 mm to9 mm, for example within a range from 7.0 mm to 8.0 mm. The centraloptical zone 14 is circumscribed by an outer annular zone, such as aperipheral zone 16 of width in a range 2.5 mm to 3.0 mm. The outerannular zone is surrounded by an outermost edge zone 18 of width in therange from 0.5 mm to 1.0 mm. The optical zone 14 is configured toprovide refractive correction and can be spherical, toric or multifocalin design, for example. The outer annular zone peripheral to the opticalzone 14 is configured to fit the corneal curvature and may compriserotational stabilization zones for translational and rotationalstability, while allowing movement of the contact lens 10 on the eye 11following blinks. The edge zone 18 may comprise a thickness within arange from 0.05 mm to 0.15 mm and may end in a wedge shape. The overalldiameter of the soft contact lens 10 can be within a range from 12.5 mmto 15.0 mm, for example within a range from 13.5 mm to 14.8 mm.

The embedded light sources 30 and the electronics are preferably locatedin the outer annular zone of the contact lens 10, as shown in FIG. 12 .The central optical zone 14 is preferably free from electronics andlight sources 30 in order to not compromise the quality of centralfoveal or macular vision, in accordance with some embodiments. In someembodiments, the edge zone 18 does not comprise circuitry in order tomaintain contact with the corneal surface and provide comfort.

The light sources can be arranged in many ways on the contact lens. Forexample, the light sources can be arranged in a substantially continuousring around the central optical zone. In some embodiments, the pluralityof light sources and the plurality of optics (e.g., lenses, mirrors orlight guides) are coupled together to form a continuous ring ofillumination.

The contact lens 10 of FIG. 12 comprises of a body composed of a softbiocompatible polymer with high oxygen permeability embedded with atransparent film populated with all the electronic and opticalcomponents. This transparent film may comprise a transparent printedcircuit board (“PCB”) substrate. The thickness of the PCB can be withina range from about 5 microns to 50 microns and may comprise a pluralityof layers of the film in order to utilize both surfaces of the PCBsubstrate for population of electronics. The PCB substrate can be curvedto conform to the geometry of the base contact lens 10, with a curvaturewithin a range about 7.5 mm to about 10.0 mm, for example within a rangefrom about 8.0 mm to about 9.5 mm, for example. The PCB substrate can beconfigured for suitable oxygen permeability. In some embodiments, thePCB is perforated to improve permeability of oxygen, tear fluid,nutrients and carbon dioxide through it. In some embodiments, the PCBhas a low tensile modulus, for example within a range from about 1 MPato about 50 MPa, although stiffer films may also be used for example. Insome embodiments, a preferred material for a transparent flexible PCBsubstrate comprises a polyimide that is cast from a liquid or asolution, and may be in the form of a polyamic acid when spin cast on aflat substrate, subsequently cured thermally to form a polyimide such asKapton™.

The contact lens 10 may comprise one or more components shown in FIG. 12. The architecture of the electronic system, shown in FIG. 12 comprisesa plurality of light sources 30 mounted on a bus, a microcontroller 38that comprises a power and data management system, an onboard memory andan RFID module, a sensor that is designed to detect a physical orphysiological trigger and issue a signal that turns the light sources 30ON or OFF, an antenna 41 for wireless exchange of data that alsofunctions as a wireless receiver of power, operating on a single ormultiple frequency bands for transmission of data and power and arechargeable solid state Lithium ion battery 20. In some embodiments,the microcontroller 38 comprises an application specific integratedcircuitry (“ASIC”). The plurality of light sources 30 may comprisemicroscopic light sources 30 as described herein.

The light sources 30 can be positioned along a circumference of diameterin the range 1.5 mm to 5.0 mm from the center.

FIG. 13 shows a ray tracing analysis of the image of a light source 30formed on an outer region of the retina 33 such as the peripheral retina33. In this simulation, the anterior chamber depth is assumed to be 4.1mm, typically between 2.9 mm and 5.0 mm for human subjects, the axiallength has been assumed to be 25.0 mm, and the contact lens 10 ispositioned on the cornea. The microscopic light source 30 is placed 1.9mm away from the center of the contact lens 10, leaving a centraloptical zone 14 of 3.8 mm in diameter that is clear.

Referring again to FIGS. 12 and 13 , a combination of a light source 30and a lens such as a micro-lens can be used to direct light to an outerregion of the retina 33. The micro-lens can be configured to collectlight emitted by the light source 30. The collected light can be one ormore of collimated or focused and directed to the pupil of the eye 11.In some embodiments, a projection system comprises the combination ofthe microlight source 30 and the image forming optics 32.

The light source 30 may comprise one or more of an organic lightemitting diode (OLED), a quantum dot light emitting diode (QLED), atransparent light emitting diode (TOLED), an inorganic light emittingdiode (i-LED) or a CRT display. The light source 30 may comprise one ormore pixels, populated on a transparent or opaque substrate. The lightsource 30 may comprise one or more display components such as a passivematrix or an active matrix, for example. In some embodiments, a size ofindividual pixels is within a range from 1 to 10 microns, for examplewithin a range from 2 to 5 microns. The brightness of each of theplurality of pixels when turned ON can be more than 500 nits (Cd/m²),more than 5000 nits, or within a range from 10,000 to 25,000 nits.

The resolving power of the retina 33 is highest at the center, thefovea. Healthy young persons are capable of angular resolution of 0.6arc minute, equivalent to 20/12 in Snellen terminology. Resolutioncapability is typically reduced to 20/200 (10 arc minute) at 25 degreeseccentricity. There are few if any cones at this eccentricity, and thepopulation of rods is also much diminished.

In some embodiments, the image delivery system provides an imageresolution equal or exceeding the level of retinal image resolution. Insome embodiments, there is no additional benefit can be expected if theprojected image resolution exceeds the resolution capability of theretina 33 at the location of the image. In some embodiments, the spotsize of the image at the retinal periphery is therefore 150 microns orless.

The wavelengths of light emitted by the light source 30 can beconfigured in many ways. The wavelength of light emitted by the lightsource 30 can be determined by clinical studies in accordance with thepresent disclosure. In some embodiments, the wavelength of the lightsource 30 comprises light that corresponds to the peak sensitivity ofretinal photoreceptors at the desired eccentricity, e.g. substantiallymatches the peak sensitivity. In some embodiments light is projected atan eccentricity of 20-30 degrees where rods are predominant, and thelight from the source comprises wavelengths within a range from aboutfrom about 420 nm to 600 nm, for example from about 490 nm to 530 nm,for example within a range from about 500 to 520 nm, for example fromabout 502 to 512 nm. In some of the wavelength simulations disclosedherein 507 nm light is used as the input wavelength parameter. Theoptical designs disclosed herein are applicable to all wavelengths, eventhough the precise results of optimized design parameters may changewith wavelength, due to chromatic dispersion of the material comprisingthe projection unit.

Work in relation to the present disclosure suggest that two designconstraints may influence the selection of design input parameters insome of the embodiments that follow. These are:

1. Dimensions of the projection unit 18, so that they can be embeddedinto the contact lens 10 without the lens thickness being too high. Insome embodiments, the maximum lens thickness in the outer annular zoneis 400 microns, which is consistent with current soft contact lenses forrefractive corrections.

2. Optical path length between the microscopic light source 30 and theimage forming system. This is related to control of image magnificationand magnitude of image blur caused by diffraction, which can bequantified as the Airy Disk diameter. Image magnification is given bythe ratio of the focal length of the image projection unit to the focallength of the eye 11, which is generally assumed to be 17 mm for firstorder estimates. In some embodiments, it is specific to the individualeye. In some embodiments, the Airy disk diameter, (2.44×λ (inmicrons)×f/≠) is no more than the retinal resolution limit at imagelocation. For example, the minimum spot size at eccentricity of 25degrees is 150 microns, so the Airy Disk diameter should not exceed 150microns and can be less than 150 microns. Since the focal length of theeye 11 is fixed, the aperture of the projection optic controls the AiryDisk diameter at any wavelength.

In some embodiments, size of the Airy Disk of the collection optics andlight sources 30 and associated image as described herein is related tothe retinal image resolution. For example, at 30 degrees, 25 degrees, 20degrees, 15 degrees and 10 degrees, the Airy Disk size may be no morethan about 150 micro-meters (“microns”, “um”) about 125 um, about 100um, about 75 um, and about 60 um, respectively.

The image forming system can be configured in many ways includingwithout limitation, diffractive optical elements, Fresnel lenses,refractive optics or reflective optics.

The following simulations provide optical results in accordance withsome embodiments disclosed herein.

TABLE 2 Input parameters of the second optical simulations. OpticalComponent or property Value Size of Light Source 10 microns MaxThickness of the light 300 microns projection unit Image location on the27° eccentric to the fovea retinal periphery Diameter of the projection1.1 mm unit Optic design Aspheric 8^(th) order, 4^(th) order Zernikepolynomials Offset between the center 1.75 mm of the contact lens andthe light projection unit Wavelength of Light 507 nm

In some embodiments, the area covered by the overall image is preferablyan arcuate segment of 5-10 degrees by 30-45 degrees, or 150-450 degree²for every light source, or about 3.0-6.0 mm² in area. In someembodiments, four such light sources 30 at each quadrant of the contactlens 10 deliver four such peripheral images for optimum neurostimulationto the retina 33. An embodiment in accordance with the secondsimulations of the image delivery system is shown in FIG. 3 . In thisembodiment, a system of convex 26 and concave 28 micro-mirrors is usedto increase optical path length and thereby image magnification of theperipheral retinal image. FIG. 4 shows the light path of the peripheralimage through the eye 11 for this embodiment. An exemplary light source30 can be defined, assuming that the diameter of the light source 30 is10 μm, and thickness is 100 μm. Four object points 40 can be specifiedto simulate the image quality, as shown in FIG. 14 . With reference toFIG. 14 , the simulated light source 30 is shown with the dashed circleof 10 μm and the simulated object points 40 includes the smaller circlesand the center points of each of the smaller circles. Table 2 shows theinput parameters of the simulation.

Output of the simulation are: Image magnification and size, Imagequality and Depth of focus. The same input and output parameters wereused to simulate all the preferred embodiments. Image size of the firstpreferred embodiment was found to be 200 microns, image magnificationbeing 20×. Results of simulation of image quality is shown in FIG. 15for this simulation. All MTF plots are virtually coincident. The MTFplots indicate that the resolution of the peripheral image issubstantially better than the limits of retinal resolution at thiseccentricity.

The depth of focus of the peripheral image was also simulated for thereflective optic in the second simulations and is shown in FIG. 16 . Insome embodiments, the image is optimally formed at a distance of 2.0 mmin front of the retina 33, causing it to be myopically defocused on theretina 33. In some embodiments, the blur induced by this myopic defocusovercomes the effect of depth of focus, so that the retina 33 perceivesa blurred image for it to perceive a neurostimulation to move forward,reducing the axial length of the eye 11. In some embodiments, the neuralstimulation is sufficient to decrease axial growth of the eye 11.

FIG. 17 shows the effect of image blur caused by myopic defocus in theform of loss of contrast or the modulus of simulated MTF plots shown fora particular spatial frequency (20/200 or 10 arc minutes) for the secondsimulations. The increase in spot size shown in FIG. 16 is reflected inand consistent with the loss of the magnitude of the MTF plots as afunction of the magnitude of myopic defocus. The second simulationsindicate that the focal length of the projection unit is 0.85 mm with animage size 200 microns and an image magnification is 20×. The Airy diskdiameter is computed to be 8.9 microns, while the Raleigh criterion is10.9 microns.

Referring again FIGS. 10A and 1 which show a lens to collect light fromthe light source 30 and direct light toward the retina 33, and the pathof light along the eye 11, respectively. In some embodiments, the lightsource 30 faces a refractive lens that approximately collimates thelight which is finally projected in front of the peripheral retina 33,creating a myopic defocus of the peripheral image. Although reference ismade to a refractive lens, other lenses can be used such as diffractiveoptics and gradient index (GRIN) lenses. Table 3 shows the designparameters of the refractive lens used for the third simulations of theperipheral image.

TABLE 3 Design input parameters of the third simulations. LensParameters Value Diameter of the light 10 microns source Wavelength usedfor 507 nm simulation Diameter of the optic 292 microns Thickness of theoptic 250 microns Refractive index of the 2.2 micro-lens Image locationon the retina 27 degrees eccentric Thickness of the projection 350microns optic Distance of light source 1.75 mm from center of contactlens Collimating lens design 14^(th) order aspheric

The results of these simulations show that the image size is 1100microns with an image magnification of 110. The MTF plots are shown inFIG. 18 for the four object points 40 shown in FIG. 14 . The magnitudeof MTF plots at high spatial frequencies are substantially lower thanthose for the reflective optic. The MTF plots show that image resolutionis adequate for image of eccentricity 27 degrees. The optical design ofthe second preferred embodiment leads to a much greater depth of focus,as shown in FIG. 19 . This means that in some embodiments the effectiveimage blur is much less for a myopic defocus in the range of 2D to 5 D,relative to the reflective optic, in accordance with the first andsecond simulations. The increased depth of focus is reflected in the MTFplots shown in FIG. 20 , which may have a lesser dependence on themagnitude of myopic defocus relative to the reflective opticconfiguration, shown in FIGS. 3 and 4 .

The third optical simulations show that the refractive optic maysuccessfully project a peripheral retinal image with an acceptable imagesize and image magnification and depth of focus. Although the imagesize, magnification and depth of focus may be somewhat larger than forthe reflective configuration of the second simulations.

Although MTF values at high spatial frequencies (50 lp/mm and above) arelower for this refractive optic design than the reflective design, imagequality at high spatial frequencies can be somewhat is less relevant atthe peripheral locations of the retinal image due to decreased visualacuity. The third simulations show that the focal length of theprojection unit is 0.15 mm with an image size of 1100 microns and animage magnification is 110×. The Airy disk diameter is computed to be36.7 microns, while the Raleigh criterion is 44.8 microns.

Referring again to FIGS. 11A and 11B, which shows a light guide, fourthsimulations were conducted for this configuration comprising a lightguide, a mirror and a lens. In the simulated embodiments, the focusinglens is located at the end (exit aperture) of the light pipe. In someembodiments, the light pipe comprises a curved lens surface on the endto focus light. In this lightguide embodiment, the projection opticcomprises a light guide comprising a mirror and a lens.

In some embodiments, the light source 30 is placed in an outer portionof the contact lens 10, e.g. near the periphery, and light from thesource is guided to a mirror that collects the light and deflects thelight towards the eye 11 to generate an image in front of the peripheralretina 33 with a myopic defocus as described herein. In someembodiments, the function of the light guide is to increase the lengthof the light path, so as to reduce image magnification and increaseresolution of the image formed anterior to the retina 33.

TABLE 4 Lens parameters used as inputs to the fourth simulations. OpticsProperty or Parameter Value Diameter of source 10 microns Wavelength ofsimulation 510 nm Length of Light Guide 2.7 mm Refractive index ofmaterial 2.2 of projection optics Diameter of mirror 400 micronsDecenter of optic relative 1.75 mm to center of contact lens Thicknessof optic 290 microns Image location 25 degrees eccentric to foveaOptical design and Image Aspheric 6^(th) order, Zernike 3^(rd) ordersimulation

Table 4 gives the properties of the projection system used in the fourthsimulations of peripheral retinal image quality formed by light guideembodiments. Image magnification was 14 with an image size of 140microns. These simulations reveal that the image magnification isacceptable, the depth of focus is not as large as the refractive optic,but larger than the reflective optic. The fourth simulations indicatethat the focal length of the projection unit is 1.21 mm with an imagesize of 140 microns and a magnification of 14×. The Airy disk diameteris computed to be 34.8 microns, while the Raleigh criterion is 42.6microns.

The three results of the second, third and fourth simulations for thethree corresponding configurations were compared with one another interms of their size, the depth of focus produced by each defining asharpness gradient of the defocused image as a function of magnitude ofmyopic defocus, and the beam diameter. The results show that the secondsimulations comprising the reflective optic has the best sharpnessgradient, while the embodiment comprising the refractive optic has thesmallest sharpness gradient, with the lightguide based projection unitproviding a limited sharpness gradient, as shown in FIG. 24 . Each ofthese approaches can be configured to decrease axial length growth inaccordance with the teachings disclosed herein.

The three embodiments also differ considerably in terms of the diameterof the optic, as shown in table 5.

TABLE 5 Optic diameters used in the three simulations. ConfigurationOptic Diameter Reflective optic 1.1 mm Refractive optic 0.3 mmLightguide optic 0.4 mm

The reflective optic and light source 30 can be configured in many ways,and additional simulations can be conducted to determine appropriateconfigurations in accordance with the teachings disclosed herein. Forexample, clarity at the central object point shown in FIG. 14 can bedisregarded because its contribution to the neurostimulation is likelyto be limited. Such simulations and optimizations can allow a reductionof the diameter of the projection unit and its thickness, which can behelpful when the system is embedded into a contact lens 10 that providesa high level of comfort to wearers as described herein. The design inputparameters for a fifth simulation are shown in Table 6. The results showthat the image magnification can be increased to 25, providing an imagesize of 250 microns for a 10 micron source, which is acceptable for aperipheral image anterior to the retina 33 in accordance with theembodiments disclosed herein. The output of these fourth imagesimulations is shown in FIGS. 25 and 26 . The sharpness gradient, thatis the variation of image spot size or MTF at a single spatial frequencyas a function of magnitude of myopic defocus are still quite acceptablewhile providing a decreased size of the projection system.

As detailed herein, the computing devices and systems described and/orillustrated herein broadly represent any type or form of computingdevice or system capable of executing computer-readable instructions,such as those contained within the modules described herein. In theirmost basic configuration, these computing device(s) may each comprise atleast one memory device and at least one physical processor.

The term “memory” or “memory device,” as used herein, generallyrepresents any type or form of volatile or non-volatile storage deviceor medium capable of storing data and/or computer-readable instructions.In one example, a memory device may store, load, and/or maintain one ormore of the modules described herein. Examples of memory devicescomprise, without limitation, Random Access Memory (RAM), Read OnlyMemory (ROM), flash memory, Hard Disk Drives (HDDs), Solid-State Drives(SSDs), optical disk drives, caches, variations or combinations of oneor more of the same, or any other suitable storage memory.

In addition, the term “processor” or “physical processor,” as usedherein, generally refers to any type or form of hardware-implementedprocessing unit capable of interpreting and/or executingcomputer-readable instructions. In one example, a physical processor mayaccess and/or modify one or more modules stored in the above-describedmemory device. Examples of physical processors comprise, withoutlimitation, microprocessors, microcontrollers, Central Processing Units(CPUs), Field-Programmable Gate Arrays (FPGAs) that implement softcoreprocessors, Application-Specific Integrated Circuits (ASICs), portionsof one or more of the same, variations or combinations of one or more ofthe same, or any other suitable physical processor.

Although illustrated as separate elements, the method steps describedand/or illustrated herein may represent portions of a singleapplication. In addition, in some embodiments one or more of these stepsmay represent or correspond to one or more software applications orprograms that, when executed by a computing device, may cause thecomputing device to perform one or more tasks, such as the method step.

In addition, one or more of the devices described herein may transformdata, physical devices, and/or representations of physical devices fromone form to another. For example, one or more of the devices recitedherein may receive image data of a sample to be transformed, transformthe image data, output a result of the transformation to determine a 3Dprocess, use the result of the transformation to perform the 3D process,and store the result of the transformation to produce an output image ofthe sample. Additionally or alternatively, one or more of the modulesrecited herein may transform a processor, volatile memory, non-volatilememory, and/or any other portion of a physical computing device from oneform of computing device to another form of computing device byexecuting on the computing device, storing data on the computing device,and/or otherwise interacting with the computing device.

The term “computer-readable medium,” as used herein, generally refers toany form of device, carrier, or medium capable of storing or carryingcomputer-readable instructions. Examples of computer-readable mediacomprise, without limitation, transmission-type media, such as carrierwaves, and non-transitory-type media, such as magnetic-storage media(e.g., hard disk drives, tape drives, and floppy disks), optical storagemedia (e.g., Compact Disks (CDs), Digital Video Disks (DVDs), andBLU-RAY disks), electronic-storage media (e.g., solid-state drives andflash media), and other distribution systems.

A person of ordinary skill in the art will recognize that any process ormethod disclosed herein can be modified in many ways. The processparameters and sequence of the steps described and/or illustrated hereinare given by way of example only and can be varied as desired. Forexample, while the steps illustrated and/or described herein may beshown or discussed in a particular order, these steps do not necessarilyneed to be performed in the order illustrated or discussed.

The various exemplary methods described and/or illustrated herein mayalso omit one or more of the steps described or illustrated herein orcomprise additional steps in addition to those disclosed. Further, astep of any method as disclosed herein can be combined with any one ormore steps of any other method as disclosed herein.

Unless otherwise noted, the terms “connected to” and “coupled to” (andtheir derivatives), as used in the specification and claims, are to beconstrued as permitting both direct and indirect (i.e., via otherelements or components) connection. In addition, the terms “a” or “an,”as used in the specification and claims, are to be construed as meaning“at least one of” Finally, for ease of use, the terms “including” and“having” (and their derivatives), as used in the specification andclaims, are interchangeable with and shall have the same meaning as theword “comprising.

The processor as disclosed herein can be configured with instructions toperform any one or more steps of any method as disclosed herein.

It will be understood that although the terms “first,” “second,”“third”, etc. may be used herein to describe various layers, elements,components, regions or sections without referring to any particularorder or sequence of events. These terms are merely used to distinguishone layer, element, component, region or section from another layer,element, component, region or section. A first layer, element,component, region or section as described herein could be referred to asa second layer, element, component, region or section without departingfrom the teachings of the present disclosure.

As used herein, the term “or” is used inclusively to refer items in thealternative and in combination.

Each embodiment disclosed herein can be combined with any one or more ofthe other embodiments disclosed herein, and a person of ordinary skillin the art will recognize many such combinations as being within thescope of the present disclosure.

The present disclosure includes the following numbered clauses:

Clause 1. An electronic contact lens to treat myopia of an eye having aretina, comprising:

a plurality of light sources; anda plurality of projection optics coupled to the plurality of lightsources to project a plurality of images anterior to the retina decreasea progression of myopia of the eye.

Clause 2. The electronic contact lens of clause 1, wherein said lens isconfigured to reverse myopia.

Clause 3. The electronic contact lens of clause 1, wherein saidplurality of projection optics is arranged to project the plurality ofimages of the plurality of light sources at a plurality of outer regionsof the retina of the eye with an eccentricity within a range from 15degrees to 30 degrees with respect to a fovea of the eye.

Clause 4. The electronic contact lens of clause 1, wherein each of saidplurality of projection optics is arranged to project an imagemyopically defocused with respect to a retinal surface, wherein anamount of said defocus is within a range from 2.0 D to 5.0 D.

Clause 5. The electronic contact lens of clause 1, wherein each of saidplurality of projection optics is located 1.5 mm to 5.0 mm from a centerof said contact lens and optionally wherein the plurality of projectionoptics is located along the circumference of a circle.

Clause 6. The electronic contact lens of clause 1, wherein saidplurality of projection optics comprises a plurality of image formingoptics optically coupled to said plurality of light sources to projectthe plurality of images anterior to the surface of the retina.

Clause 7. The electronic contact lens of clause 6, wherein each of saidplurality of light sources has a maximum distance across not exceeding26 microns and optionally no more than 10 microns and optionally whereinsaid maximum distance across comprises a diameter.

Clause 8. The electronic contact lens of clause 6, wherein each of theplurality of projection optics comprises one or more of a mirror, alens, or a lightguide.

Clause 9. The electronic contact lens of claim 8, wherein each of theplurality of image forming optics comprising one or more of adiffractive element, a Fresnel lens, or a compound Gabor lens.

Clause 10. The electronic contact lens of clause 8, wherein each of theplurality of image forming optic has a maximum distance across within arange from 1.5 mm to 200 microns and optionally wherein said maximumdistance across comprises a diameter.

Clause 11. The electronic contact lens of clause 8, wherein each of theplurality of image forming optics is aspheric and corrected for imageaberrations.

Clause 12. The electronic contact lens of clause 8, wherein each of theplurality of image forming optics comprises a combination of convex andconcave mirrors.

Clause 13. The electronic contact lens of clause 11, wherein said eachof the plurality of image forming optic forms an image anterior to anouter portion of the retina at an eccentricity within a range from 15degrees to 30 degrees from a fovea and optionally within a range from 25degrees to 30 degrees from the fovea.

Clause 14. The electronic contact lens of clause 11, wherein said eachof the plurality of image forming optics creates an image anterior tothe retina with an image of magnification within a range from 25 to 100.

Clause 15. The electronic contact lens of clause 1, wherein the imageanterior to the outer portion of the retina comprises magnitude ofmodulation transfer function of no less than 0.75 at a spatial frequencyof 10 lp/mm, and no less than 0.40 at a spatial frequency of 50 lp/mm.

Clause 16. The electronic contact lens of clause 8, wherein each of theplurality of projection optics comprises an image forming opticcomprising a collimating optic configured to form the image anterior tothe retina.

Clause 17. The electronic contact lens of clause 8, wherein saidprojection optic comprises a single lens to function both as acollimating optic and an image forming optic.

Clause 18. The electronic contact lens of clause 8, wherein saidprojection optic comprises an image forming optic to create an imageanterior to an outer portion of the retina with eccentricity no morethan 30 degrees and a depth of focus of no more than 1.0 D.

Clause 19. The electronic contact lens of clause 17, wherein said opticcreates the image anterior to an outer portion of the retain with aneccentricity no more than 30 degrees, wherein a modulation transferfunction of said image decreases by a minimum of 0.1 units for a defocusof 1.0 diopters.

Clause 20. A soft contact lens comprising:

a plurality of light sources coupled to a plurality of optical elements,the plurality of light sources and the plurality of optical elementsembedded in a soft contact lens material, wherein each of said pluralityof optical elements generates an image focused in front of a peripheralretina of a wearer.

Clause 21. The soft contact lens of clause 20, wherein the plurality oflight sources comprises a plurality of micro-displays.

Clause 22. The soft contact lens of clause 20, wherein the plurality oflight sources comprises a plurality of light emitting diodes (LEDs).

Clause 23. The soft contact lens of clause 20, wherein each of saidplurality of optical elements comprises a mirror assembly thatcollimates light emitted by a corresponding micro-display and directs aresulting light beam into the pupil of the eye, wherein said light beamis focused to form the peripheral image in front of the retina.

Clause 24. The soft contact lens of clause 20, wherein each of saidplurality of optical elements comprise a lens that receives lightemitted by a corresponding microdisplay and directs a resulting lightbeam into the pupil of the eye, wherein said light beam is focused toform an image in front of the retina.

Clause 25. The soft contact lens of clause 20, wherein said theplurality of light sources generates a polychromatic illumination andoptionally wherein the plurality of light sources comprises a pluralityof micro-displays generating polychromatic illumination.

Clause 26. The soft contact lens of clause 20, wherein said image isabout 0.5 mm to 2.0 mm in front of the retina.

Clause 27. The soft contact lens of clause 20, wherein said image has aresolution of at least 30 lp/mm.

Clause 28. The soft contact lens of clause 20, wherein said image has amagnification of no more than 100×.

Clause 29. The soft contact lens of clause 20, wherein said image has adepth of focus no more than 2.5 diopters and optionally wherein saiddepth of focus is no more than about 0.9 mm.

Clause 30. The soft contact lens of clause 20, wherein said image isprojected at an eccentricity in the within a range from about 15 degreesto about 45 degrees.

Clause 31. The soft contact lens of clause 30, wherein said range isfrom about 25 degrees to about 30 degrees.

Clause 32. The soft contact lens of clause 20, wherein saidmicro-display illuminates the pupil with an illuminance within a rangefrom about 0.1 cd/m² to 10 cd/m².

Clause 33. The soft contact lens of clause 20, wherein the image isfocused at a distance in front of the peripheral retina at a locationand the image comprises a depth of focus and a spatial resolution, thedepth of focus less than the distance, the spatial resolution greaterthan a spatial resolution of the peripheral retina at the location.

Clause 34. The soft contact lens of clause 20, further comprising asensor to receive input from the wearer when the contact lens has beenplaced on an eye of the wearer.

Clause 35. The soft contact lens of any one of the preceding clauses,further comprising a processor coupled to the plurality of light sourcesto control illumination of the plurality of light sources.

Clause 36. The soft contact lens of any one of the preceding clauses,further comprising wireless communication circuitry operatively coupledto the plurality of light sources to control illumination of theplurality of light sources.

Clause 37. The soft contact lens of any one of the preceding clauses,further comprising wireless communication circuitry operatively coupledto a mobile device for the wearer to control illumination of theplurality of light sources.

Clause 38. The soft contact lens of any one of the preceding clauses,further comprising wireless communication circuitry operatively coupledto a processor for a health care provider to program illumination cyclesand intensities of the plurality of light sources.

Clause 39. A soft contact lens embedded with at least one micro-displaywherein said micro-display generates an image that is focused in frontof the peripheral retina of a wearer.

Clause 40. The lens of clause 39, wherein said lens provides bestrefractive correction to refractive errors of the wearer.

Clause 41. The lens of clause 39, wherein said micro-display isdisplaced from the optical center of said lens by about 2.5 mm to about5.0 mm.

Clause 42. The lens of clause 39, wherein it comprises a set of 4 to 8microdisplays, disposed evenly along an arc of said lens, each beingdisplaced equally from the optical center of said lens.

Clause 43. The lens of clause 39, wherein said image is focused 0.5 mmto 2.5 mm in front of the retina.

Clause 44. The lens of clause 39, wherein said image is focused 1.0 D to3.0 D myopically relative to the best focus at the fovea of the wearer.

Clause 45. The lens of clause 39, wherein said lens comprises at leastone microdisplay, an ASIC, a voltage ramp, a rechargeable battery, awireless receiver and transmitter, a flash memory and a non-volatilememory.

Clause 46. The lens of clause 39, wherein said micro-display is amicro-OLED.

Clause 47. The lens of clause 39, wherein said micro-display is amicro-LED.

Clause 48. The lens of clause 39, wherein said micro-display isoptically coupled with a micro-lens array.

Clause 49. The lens of any one of clauses 39 or 45, wherein said arrayshave dimensions ranging from 1 mm² to 8 mm² and optionally from 1 mm² to8 mm².

Clause 50. The lens of clause 39, wherein the duration of said image ofclause 1 is programmable when the lens is on eye.

Clause 51. The lens of clause 47, wherein said image is projectedcontinuously for about 1 hour to about 12 hours per day.

Clause 52. The lens of clause 47, wherein said image is projectedepisodically, several times a day, with the total duration of projectionranging from 1 hour to 12 hours per day.

Clause 53. The lens of clause 39, wherein said image is projected whenthe wearer is asleep.

Clause 54. The lens of clause 39, wherein said image is monochromatic,preferably at 500 nm.

Clause 55. The lens of clause 39, wherein said image is polychromatic,with a wavelength distribution that preferably matches the retinalresponse to visible light.

Clause 56. The lens of clause 39, wherein said lens is of dailydisposable modality.

Clause 57. The lens of clause 39, wherein said lens is of plannedreplacement modality.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. It is not intendedthat the invention be limited by the specific examples provided withinthe specification. While the invention has been described with referenceto the aforementioned specification, the descriptions and illustrationsof the embodiments herein are not meant to be construed in a limitingsense. Numerous variations, changes, and substitutions will now occur tothose skilled in the art without departing from the invention.Furthermore, it shall be understood that all aspects of the inventionare not limited to the specific depictions, configurations or relativeproportions set forth herein which depend upon a variety of conditionsand variables. It should be understood that various alternatives to theembodiments of the invention described herein may be employed inpracticing the invention. It is therefore contemplated that theinvention shall also cover any such alternatives, modifications,variations or equivalents. It is intended that the following claimsdefine the scope of the invention and that methods and structures withinthe scope of these claims and their equivalents be covered thereby.

What is claimed is:
 1. An apparatus to treat myopia of an eye having a retina, comprising: a lens; a plurality of light sources; and a plurality of projection optics coupled to the plurality of light sources to project a plurality of light spots on an outer region of the retina to decrease a progression of myopia of the eye.
 2. The apparatus of claim 1, wherein said apparatus is configured to reverse myopia.
 3. The apparatus of claim 1, wherein said plurality of projection optics is arranged to project the plurality of light spots from the plurality of light sources at a plurality of outer regions of the retina of the eye with an eccentricity within a range from 15 degrees to 30 degrees with respect to a fovea of the eye.
 4. The apparatus of claim 1, wherein each of said plurality of projection optics is arranged to project an image myopically defocused with respect to a retinal surface, wherein an amount of said defocus is within a range from 2.0 D to 5.0 D.
 5. The apparatus of claim 1, wherein each of said plurality of projection optics is located 1.5 mm to 5.0 mm from a center of said contact lens.
 6. The apparatus of claim 1, wherein the plurality of light spots comprises a plurality of defocused images on the outer region of the retina and wherein said plurality of projection optics is optically coupled to said plurality of light sources to project the plurality of images to a focus anterior to a surface of the retina to form the plurality of defocused images on the plurality of outer regions of the retina.
 7. The apparatus of claim 6, wherein each of said plurality of light sources has a maximum distance across not exceeding 26 microns.
 8. The apparatus of claim 6, wherein each of the plurality of projection optics comprises one or more of a mirror, a lens, a diffractive element, a Fresnel lens, a compound Gabor lens, a lightguide, or a wave guide.
 9. The apparatus of claim 8, wherein each of the plurality of projection optics is coupled to a corresponding light source among the plurality of light sources to form an image anterior to an outer portion of the retina and wherein a modulation transfer function of said image decreases by a minimum of 0.1 units for a defocus of 1.0 diopters.
 10. The apparatus of claim 8, wherein each of the plurality of projection optics has a maximum distance across within a range from 1.5 mm to 200 microns.
 11. The apparatus of claim 8, wherein each of the plurality of projection optics is aspheric and corrected for image aberrations.
 12. The apparatus of claim 8, wherein each of the plurality of projection optics comprises a combination of convex and concave mirrors.
 13. The apparatus of claim 11, wherein said each of the plurality of projection optics forms an image anterior to an outer portion of the retina at an eccentricity within a range from 15 degrees to 30 degrees from a fovea.
 14. The apparatus of claim 11, wherein said each of the plurality of projection optics creates an image anterior to the retina with an image of magnification within a range from 25 to
 100. 15. The apparatus of claim 6, wherein the plurality of images focused anterior to the outer portion of the retina comprises magnitude of modulation transfer function of no less than 0.75 at a spatial frequency of 10 lp/mm, and no less than 0.40 at a spatial frequency of 50 lp/mm, in order to form the plurality of defocused images on the outer portion of the retina.
 16. The apparatus of claim 8, wherein each of the plurality of projection optics comprises a collimating optic configured to form the image anterior to the retina.
 17. The apparatus of claim 8, wherein each of the plurality of projection optics comprises a single lens to function both as a collimating optic and an image forming optic.
 18. The apparatus of claim 8, wherein each of the plurality of projection optics is coupled to a corresponding light source among the plurality of light sources to create an image anterior to an outer portion of the retina with eccentricity no more than 30 degrees and a depth of focus of no more than 1.0 D.
 19. The apparatus of claim 1, wherein said plurality of light sources comprises from 4 to 8 micro-displays, disposed evenly along an arc of said lens, each being displaced equally from an optical center of said lens. 